Imaging of the pial arterial vasculature of the human brain in vivo using high-resolution 7T time-of-flight angiography
- The University of Queensland, Australia
- Otto-von-Guericke University Magdeburg, Germany
- Massachusetts General Hospital, United States
- German Center for Neurodegenerative Diseases, Germany
- Harvard Medical School, United States
Abstract
The pial arterial vasculature of the human brain is the only blood supply to the neocortex, but quantitative data on the morphology and topology of these mesoscopic arteries (diameter 50-300µm) remains scarce. Because it is commonly assumed that blood flow velocities in these vessels are prohibitively slow, non-invasive time-of-flight MRI angiography (TOF-MRA)-which is well-suited to high 3D imaging resolutions-has not been applied to imaging the pial arteries. Here, we provide a theoretical framework that outlines how TOF-MRA can visualize small pial arteries in vivo, by employing extremely small voxels at the size of individual vessels. We then provide evidence for this theory by imaging the pial arteries at 140-µm isotropic resolution using a 7T MRI scanner and prospective motion correction, and show that pial arteries one voxel-width in diameter can be detected. We conclude that imaging pial arteries is not limited by slow blood flow, but instead by achievable image resolution. This study represents the first targeted, comprehensive account of imaging pial arteries in vivo in the human brain. This ultra-high-resolution angiography will enable the characterization of pial vascular anatomy across the brain to investigate patterns of blood supply and relationships between vascular and functional architecture.
Data availability
The anonymized imaging data presented in this manuscript are stored in OSF (OSF, Center for Open Science, Inc., Charlottesville, Virginia, USA) accessible via https://osf.io/nr6gc/.
Article and author information
Author details
Jonathan R Polimeni
Funding
National Institute of Biomedical Imaging and Bioengineering (P41-EB015896)
- Jonathan R Polimeni
National Institutes of Health (S10-RR019371)
- Jonathan R Polimeni
National Institutes of Health (S10-OD02363701)
- Jonathan R Polimeni
European Commission (MS-fMRI-QSM 794298)
- Simon D Robinson
National Institute of Biomedical Imaging and Bioengineering (P41-EB030006)
- Jonathan R Polimeni
National Institute of Biomedical Imaging and Bioengineering (R01-EB019437)
- Jonathan R Polimeni
National Institute of Neurological Disorders and Stroke (R21-NS106706)
- Jonathan R Polimeni
National Institute of Mental Health (R01-MH111438)
- Saskia Bollmann
National Institute of Mental Health (R01-MH111419)
- Saskia Bollmann
Natural Sciences and Engineering Research Council of Canada
- Michaël Bernier
Fonds de recherche du Québec – Nature et technologies
- Michaël Bernier
Deutsche Forschungsgemeinschaft (MA 9235/1-1)
- Hendrik Mattern
- Oliver Speck
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Four healthy adults volunteered to participate in the study (four males, ages 30-46). Prior to imaging, written informed consent was obtained from the three participants scanned in Boston (Figure 5, 6, 8 and 9 and corresponding figure supplements) in accordance with the Partners Human Research Committee and the Massachusetts General Hospital Institutional Review Board (protocol #2016P000274); after the study completion, a consent form addendum was used to obtain informed consent from each participant specifically to share their anonymized data on a public data repository. For the single subject from Magdeburg (Figure 7 and corresponding figure supplements) the consent to share openly the data in anonymized form was acquired prospectively (facultative option in study consent form) in accordance with the 'Ethikkommission Otto-von-Guericke-Universität Magdeburg' (protocol 15/20).
Copyright
© 2022, Bollmann et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Imaging of the pial arterial vasculature of the human brain in vivo using high-resolution 7T time-of-flight angiography
eLife 11:e71186.
https://doi.org/10.7554/eLife.71186
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